The goals of the proposed research are to determine the location and aspects of this problem are currently being investigated. Control of gene yeast glyceraldehyde-e-phosphate dehydrogenase (GAPDH) and enolase genes. have studied the mechanisms of transcriptional control in tow bacterial be based on the primary structures of the three GAPDH and two enolase genes the control of the programmed pattern of transcriptional initiation during plasmids containing coding region deletions, constructed in vitro, be used control of expression and the function of the actin gene in S. cerevisiae. transformation and gene replacement. A mutant strain containing a deletion reactions collectively known as RNA processing. It is now clear that RNA already been isolated using the replacement method. Mutants containing recent elucidation of eukaryotic gene structures has revealed a new analyze expression of each gene repeat. The expression of GAPDH and non-coding sequences known as intervening sequences or introns. These sequences present in the 5' and 3' noncoding regions of the genes determine called RNA splicing. We are the first to demonstrate the RNA splicing gene fusion containing the 5' noncoding sequences of a GAPDH gene and the continuing the study of the tRNA splicing reaction and propose procedures 5' noncoding sequences are responsible for the efficiency of expression of recently been developed allowing the in vitro alteration of genes and their noncoding sequences of enolase and GAPDH genes will be constructed in vitro mutagenic strategies requires the organic synthesis of oligonucleotides by integration of the mutant gene at its proper locus in the yeast genome. to use these techniques to synthesize oligonucleotides to produce precise noncoding regions of the gene. Rapid quantitative assays for the synthesis. gene have been developed. Finally, it is proposed that sequences required for RNA polymerase I dependent site specific initiation of transcription in vitro on cloned yeast ribosomal genes be identified by targeted in vitro mutagenesis and that components required for selective transcription by RNA polymerase I be fractionated. The long term goal of this investigation will be in vitro reconstitution of selective transcription of yeast glycolytic and ribosomal genes.